Minimally invasive surgery. Endoscopic parathyroidectomy. Experimental study in the dog

The first parathyroidectomy was performed in Vienna, Austria, in 1925. Laparoscopic procedures were initially limited to body areas with preexisting cavities; more recently, access to potential spaces has extended the spectrum of minimally invasive endoscopic surgery. Since the first report of an endoscopic parathyroidectomy in 1996, the video-assisted techniques have been applied to surgery of the neck, and several series have documented the feasibility. The purpose of the present study was to develop techniques for obtaining endoscopic exposure and access to the pretracheal space in the neck with the goal of performing parathyroidectomy and evaluates the safety and efficacy of such and approach experimentally. The technique for endoscopic parathyroidectomy was performed in 31 adult mongrel dogs. The pretracheal space was accessed by a 2, 5 cm midline incision in the lower neck. The space was expanded with a balloon dissector. A 5 or 10/12 mm midline port and two to four lateral 5 mm cervical ports were placed, and dissection was carried out with endoscopic instruments. Excised parathyroid tissue was verified histologically. The parathyroidectomy was successfully completed in all dogs, inadequate exposure led to a failed procedure in one animal. Mean operative time was 125 +/- 12 minutes, and there were no operative complications. Serum calcium levels did not change significantly after operation. At autopsy, approximately 10 ml of clear sterile fluid was present in the pretracheal space of every dog. Parathyroidectomy may be performed safely and reliably in an animal model with minimally invasive techniques that can be applied in the human.